Trigger locking means for hand-portable power-operated device



July 13, 1965' A. H. FILANDER 3,

TRIGGER LOCKING MEANS FOR HAND-PORTABLE PbWERvOPERATED DEVIGE Filed Jan. 2;, 1963 ftm lii INVENTOR ARTHUR H. FILANDER LOCK ON BY im flea ATTORNEY United States Patent 3,194,084 TRIGGER LGCKHJG MEANS FUR HAND-IGRT ABLE PIIWER=0PERATED DEVICE Arthur H. Filander, Baltimore, Md assignor to The Black and Decker Manufacturing Company, Tow/son, Md, a

corporation of Maryland Filed Jan. 21, 1963, her. No. 252,7tl 2 Claims. (Cl. 7t527) The present invention relates to a trigger locking means for a slidable trigger used in a hand-portable power-operated device, and more particularly, to a means for locking the trigger either in its on position or in its olI position.

It is an object of the present invention to provide a locking means for a slidable trigger used in a handportable power-operated device, such as a cordless electric drill, wherein the slidable trigger may be either locked in its on position or in its off position, and wherein the locking means comprises a locking pin passing through an aperture formed within the trigger member, with the locking pin being movable transversely to the plane of movement of the trigger.

It is another object of the present invention to provide a trigger, slidable on respective guideways formed in the housing, in combination with means for locking the trigger in either of its positions.

It is yet another object of the present invention to provide a combination of a slidable trigger and a trigger locking means; wherein the overall combination may be manufactured easily and economically, manipulated conveniently, and used repeatedly without breakdown or failure.

In accordance with the general teachings of the present invention, there is herein illustrated and described a trigger locking means for a hand-portable power-operated device of the type having an housing and further having a trigger slidable in the housing to actuate the device. The trigger normally has an off position in which the device is tie-energized; and the trigger further has an on position, retracted with respect to the housing, in which the device is energized. A slotted aperture is formed in the trigger, and a stop is formed intermediate the extremities of the aperture. A locking pin is journaled in the housing for sliding movement transversely of the trigger, and the locking pin normally has an unlocked position and alternately has a locked position with respect to the trigger. The locking pin passes through the aperture in the trigger; and the locking pin is formed with an intermediate portion of reduced diameter which is normally received within the rear portion of the slotted aperture in the trigger; consequently, and whenever the trigger is moved into its on position, the stop in the aperture passes freely and is not impeded by the intermediate portion of the locking pin. The locking pin is further formed with a portion, which is adjacent to its intermediate portion, and which has a diameter larger than the reduced diameter of the intermediate portion of the pin. Whenever the locking pin is moved to its locked position, this adjacent portion of the locking pin abuts against the stop formed within the aperture of the trigger. Consequently, the locking pin thereafter prevents further movement of the trigger, either inwardly or outwardly of the housing, so as to lock the trigger in either its on position or in its off position.

These and other objects of the present invention will become apparentfrom a reading of the following specification, taken in conjunction with the enclosed drawings, in which:

FIGURE 1 is a side elevation of a typical hand-portable power-operated device with which the teachings of the present invention may find more particular utility;

FIGURE 2 is an enlarged fragmentary portion of FIG- URE 1, with parts broken away and sectioned, showing the spring-biased sliding trigger and the slotted aperture formed therein, and further showing the transverse looking pin in section;

FIGURE 3 is a section View taken along the lines 33 of FIGURE 2, showing the ribs formed integrally on the sliding trigger, and further showing the cooperating respective guideways formed in the housing;

FIGURE 4 is a View taken along the lines 4-4 of FIGURE 2, showing the contact bar carried by the sliding trigger switch for engaging the cantilevered leaf-spring contacts;

FIGURE 5 is a stepped section view taken along the lines 55 of FIGURE 2, showing the sliding locking pin in its unlocked position with respect to the trigger;

FIGURE 6 is a section view taken along the lines s s of FIGURE 2, showing more particularly the slotted aperture formed within the trigger member;

FIGURE 7a is an enlarged view of a portion of FIG- URE 2, with the sliding trigger in elevation and the locking pin in section, and showing the switch in its ofF position and the lock also in its off position;

FIGURE 7b is a view corresponding substantially to that of FIGURE 7a, but showing the switch in its on position and the lock in its ofFposition;

FIGURE 70 is a corresponding view, showing the switch locked in its on position; and

FIGURE 7d is a corresponding view, showing the switch locked in its oil position.

With reference to FIGURE 1, there is illustrated a portable cordless electric drill to with which the teachings of the present invention may find more particular utility; however, it will be understood and appreciated by one skilled in the art that the essence of the present invention is not necessarily confined thereto, but rather comprises a wide variety of power tools, appliances, and devices. With this in mind, the drill 1% comprises a motor housing 11, a gear case 12 secured forwardly of the motor housing 11, a conventional chuck 13, a handle housing 14 secured rearwardly of the motor housing 11, an auxiliary battery case 15 depending from the handle housing 14, with the removable battery pack (not shown) being housed mutually between the handle housing 14 and its associated battery case 15, and a sliding trigger 16 mounted within the handle housing 14 and adapted to be locked either in its on position or in its off position by means of a locking pin 17 slidable transversely of the trigger.

With reference to FIGURES 2 and 3, the sliding trigger 16 may be molded from a suitable insulating material, and the trigger 16 has a pair of integrally-formed longitudinal ribs 13 adapted to be received within respective longitudinal slotted guideways 19 formed in the handle housing I4, thereby guiding the sliding trigger I6. The trigger In normally has a forward position with respect to the housing, see FIGURE 2, wherein the switch is in its oil position and the drill 1.6 is thus deenergized; and the trigger In further has a retracted position with respect to the housing, wherein the switch is in its alternate or on position and the drill is thus energized. The trigger 16 is normally biased to its off position by means of a spring 26 seated within a recess 21 formed within the rear portion of the trigger 16. A contact bar 22 is mounted upon the trigger 16 by means of a screw 23, and a pair of cantilevered leaf-spring contacts 24; are mounted within the housing and carry respective electrical contact buttons 25. Thus, whenever the trigger 15 is retracted within the housing, the

contact bar 22 bridges the contacts 25; and the switch is closed for energizing the drill 10.

With reference to FIGURES 4, 5, and 6, the trigger 16 is formed with a slotted aperture 26, and the aperture is provided with a narrowed-down stop portion 27 intermediate its forward and rearward portions. A sliding locking pin 28 is journalecl within the handle housing 14 and passes through the slotted aperture 26 for movement transverse with respect to the trigger 16. Twoposition detent means are provided between the sliding locking pin'28 and the handle housing 14. This detent means comprises a resilient O-ring 29 retained within a counterbore 30 of the handle housing 14 by means of a press-fitted bushing 31. A pair of spaced-apart parallel external annular grooves 32 and 33 are formed on .the locking pin 28, and the combination of the grooves 32 and 33 and the O-ring 29 provides a spring-loaded snap action for the sliding movement of the locking pin 23. The opposite end of the locking pin 28 carries a lock washer 34 and an internally-threaded locking cap 35, and the pin 28 is thus provided with end portions which project beyond the respective sides of the housing 14 for convenient manipulation by the user. The locking pin 28 has an intermediate portion 36 (of substantially-reduced diameter) which is normally received and the locking pin 28 is also in its off position, with the reduced intermediate portion 36 of the pin being received within the rear portion of the slotted aperture 26 formed in the trigger 16. In FIGURE 7b, the trigger 16 has been slidably retracted within the handle housing 14, against the tension of spring 20, such that the intermediate narrowed-down stop portion 27 of the aperture 26 has easily cleared the reduced portion 36 of the locking pin 28, and such that the reduced portion 36 is now received within the forward portion of the aperture. The switch is in its on position, with the drill being energized, while the lock remains in its ofl position. If it is then desired to maintain the switch in its on position, as shown in FIGURE 70, the sliding locking pin 28 is moved (transversely of the trigger 16) into its locked position, such that its portion 37 is received to the reduced intermediate portion 36) is received Within the forward portion of the slotted aperture 26. In such a position, the portion 37 of the locking pin 28 will abut against one side of the stop 27 in the aperture 26 to prevent the return of the trigger 16 to its normal position; and hence the switch is locked in its on position. This may be particularly useful when the 'drill is being used for extended periods of time, such that the operator will no longer be required to manually and continually depress the trigger. The trigger cannot return to its off position until the locking pin 28 has first been moved back to its unlocked position. Finally, in FIGURE 7d, the trigger 16 is initially in its normal position with respect to the housing, and the switch is off; and if it is desired to maintain the switch in this position, then the sliding locking pin 28 is moved to its locked position, such that its portion 37 is received within the rear portion of the slotted aperture 26. In

such a position, the portion 37 of the locking pin 28 will abut against the stop 27 in the aperture 26 to prevent the retraction of the sliding trigger 16 to its on position, and thus the switch is locked in its off position. When the drill 10 is of the cordless type, this feature may be useful either as a safety factor or as a means for preventing the inadvertent closing of the switch and the consequent depletion of its battery when the drill 1s not being used.

Obviously, many modifications may be made without departing from the basic spirit of the present invention; and accordingly, within the scope of the appended claims, the invention may be practiced other than has been specifically described.

I claim:

1. In a hand-portable power-operated device, the combination of:

(a) a housing;

(b) a trigger slidable in said housing;

(c) said trigger normally having an off position in which the device is de-energized and further having an alternate on position, retracted with respect to said housing, and in which the device is energized;

(d) a slotted aperture formed in said trigger;

(e) a stop formed intermediate the extremities of said aperture, and said aperture having forward and rearward portions on respective sides of said stop;

(f) a locking member slidable in said housing and passing transversely through said aperture in said trigger, said locking member normally having an unlocked position and alternately having a locked position with respect to said trigger; and said locking member requiring a deliberate manual effort for movement from its unlocked position to its locked position, and vice-versa;

(g) said locking member having an intermediate portion of reduced cross-section normally received within said rearward portion of said slotted aperture in said trigger in the unlocked position of said locking member, whereby said stop in said aperture moves freely past said intermediate portion when said trigger is moved into its on position, and whereby said intermediate portion of said locking pin is received within said forward portion of said aperture in the on position of said trigger; and

(h) said locking member further having a second portion adjacent said intermediate portion, said secend portion having an increased cross-section over said intermediate portion and being adapted to abut against a respective end of said stop, when said pin is moved into its locked position, to thereafter prevent further movement of said trigger, and to thereby lock said trigger in either of its positions.

2. The combinations according to claim 2, wherein said locking member comprises:

(a) a locking pin journaled for sliding movement in said housing; and wherein (b) said intermediate portion of said pin comprises a portion of reduced diameter.

References Cited by the Examiner UNITED STATES PATENTS 2,200,322 5/40 Arnesen 200-157 2,487,011 11/49 Wilhide 200157 2,503,226 4/50 Turner et al 200157 2,815,016 12/57 Kellogg 12440 X 2,922,012 1/60 OMara 200-157 2,988,724 6/61 Larkin 200-157 3,061,334 10/62 Everett et al 292- 3,132,227 5/64 Butler 200-157 BROUGHTON G. DURHAM, Primary Examiner. BERNARD A. GILHEANY, Examiner. 

1. IN A HAND-PORTABLE POWER-OPERATED DEVICE, THE COMBINATION OF: (A) A HOUSING; (B) A TRIGGER SLIDABLE IN SAID HOUSING; (C) SAID TRIGGER NORMALLY HAVING AN "OFF" POSITION IN WHICH THE DEVICE IS DE-ENERGIZED AND FURTHER HAVING AN ALTERNATE "ON" POSITION, RETRACTED WITH RESPECT TO SAID HOUSING, AND IN WHICH THE DEVICE IS ENERGIZED; (D) A SLOTTED APERTURE FORMED IN SAID TRIGGER; (E) A STOP FORMED INTERMEDIATE THE EXTREMITIES OF SAID APERTURE, AND SAID APERTURE HAVING FORWARD AND REARWARD PORTIONS ON RESPECTIVE SIDES OF SAID STOP; (F) A LOCKING MEMBER SLIDABLE IN SAID HOUSING AND PASSING TRANSVERSELY THROUGH SAID APERTURE IN SAID TRIGGER, SAID LOCKING MEMBER NORMALLY HAVING AN "UNLOCKED" POSITION AND ALTERNATELY HAVING A "LOCKED" POSITION WITH RESPECT TO SAID TRIGGER; AND SAID LOCKING MEMBER REQUIRING A DELIBERATE MANUAL EFFORT FOR MOVEMENT FROM ITS "UNLOCKED" POSITION TO ITS "LOCKED" POSITION, AND VICE-VERSA; (G) SAID LOCKING MEMBER HAVING AN INTERMEDIATE PORTION OF REDUCED CROSS-SECTION NORMALLY RECEIVED WITHIN SAID REARWARD PORTION OF SAID SLOTTED APERTURE IN SAID TRIGGER IN THE "UNLOCKED" POSITION OF SAID LOCKING MEMBER, WHEREBY SAID STOP IN SAID APERTURE MOVES FREELY PAST SAID INTERMEDIATE PORTION WHEN SAID TRIGGER IS MOVED INTO ITS "ON" POSITION, AND WHEREBY SAID INTERMEDIATE PORTION OF SAID LOCKING PIN IS RECEIVED WITHIN SAID FORWARD PORTION OF SAID APERTURE IN THE "ON" POSITION OF SAID TRIGGER; AND (H) SAID LOCKING MEMBER FURTHER HAVING A SECOND PORTION ADJACENT SAID INTERMEDIATE PORTION, SAID SECOND PORTION HAVING AN INCREASED CROSS-SECTION OVER SAID INTERMEDIATE PORTION AND BEING ADAPTED TO ABUT AGAINST A RESPECTIVE END OF SAID STOP, WHEN SAID PIN IS MOVED INTO ITS "LOCKED" POSITION, TO THEREAFTER PREVENT FURTHER MOVEMENT OF SAID TRIGGER, AND TO THEREBY LOCK SAID TRIGGER IN EITHER OF ITS POSITIONS. 